Generator voltage regulator with detachable resistance unit in the voltage reference circuit

ABSTRACT

A voltage regulator adjustment device including a plurality of series-connected resistors contained in a body having two sets of terminals for removable connection with other structures. One set of terminals is adapted for connection with a conductor contained in a cap so as to short any of the resistors in the body. The other set of terminals is removably connected across terminals of an otherwise inaccessible voltage regulator located in the housing of an alternator, thereby inserting the resistors of the body into a voltage divider contained in the regulator. A reference point in the voltage divider is operatively connected to an output transistor in the regulator to control the output of the alternator in accordance with the voltage at the reference point. Therefore, by adding the resistors of the body and shorting those desired with the conductor in the cap, the voltage setting of the voltage regulator is in effect altered to provide a different output voltage for the alternator.

United States Patent Alexander et a1.

[54] GENERATOR VOLTAGE REGULATOR WITH DETACHABLE RESISTANCE UNIT IN THEVOLTAGE REFERENCE CIRCUIT [72] Inventors: Arthur W. Alexander; Glen R.Renner,

both of Anderson, Ind.

[73] Assignee: General Motors Corporation, Detroit,

Mich.

[22] Filed: Apr. 16,1970

211 App]. No.: 29,151

52 U.S. c1 ..322/28, 310/71, 310/72, 322/73, 322/83, 338/48, 338/221 511111. C1. ..H02p 9/30 [58] Field of Search ..322/28, 73, 80, 83, 85;310/71, 72; 323/94, 96, 97; 318/345; 338/48, 76,

1451 Apr. 25, 1972 Primary Examiner-Lewis H. Myers Assistant Examiner-H.l-luberfeld Atto ney-C. R. Meland, E. W. Christen and Albert F. Duke 57ABSTRACT A voltage regulator adjustment device including a plurality ofseries-connected resistors contained in a body having two sets ofterminals for removable connection with other structures. One set ofterminals is adapted for connection with a conductor contained in a capso as to short any of the resistors in the body. The other set ofterminals is removably connected across terminals of an otherwiseinaccessible voltage regulator located in the housing of an alternator,thereby inserting the resistors of the body into a voltage dividercontained in the regulator. A reference point in the voltage divider isoperatively connected to an output transistor in the regulator tocontrol the output of the alternator in accordance with the voltage atthe reference point. Therefore, by adding the resistors of the body andshorting those desired with the conductor in the cap, the voltagesetting of the voltage regulator is in effect altered to provide adifferent output voltage for the alternator.

2 Claims, 9 Drawing Figures Patented April 25, 1972 3, 659,188

2 Sheets-Sheet l A TTOHN/IV Sheets-Sheet z A TTORNEY GENERATOR VOLTAGEREGULATOR WITH DETACHABLE RESISTANCE UNIT IN THE VOLTAGE REFERENCECIRCUIT This invention relates to shortable resistance means removablyconnected to terminals of an otherwise inaccessible voltage regulator ofa generator-supplied battery charging system for changing the outputthereof.

Diode-rectified altemators and regulators for battery charging systemshave heretofore been either designed or manufactured specifically fordifferent applications or have required internal adjustments of outputsettings to accommodate usages under various conditions of temperature,duty, and installation. In the case of a passenger vehicle, the primaryfactor necessitating adjustment is the local temperature to which thebattery is exposed. Since the internal resistance of the battery variesinversely with the temperature, the charging voltage must also beadjusted to vary inversely with the temperature in order to maintain anadequate charge state on the battery.

Adjustment of the charging voltage in a typical passenger vehicle iseffected automatically through the action of a thermistor in theregulator circuit controlling the battery charging voltage in the caseof a transistor voltage regulator. This is possible because theregulator and the battery are both in the engine compartment and arethere exposed to substantially the same temperature variations. Thetemperature seen by the thermistor thus correlates with the temperatureseen by the battery so that the change in output voltage resulting fromthe change of voltage regulator setting varies properly with the changeof internal battery resistance.

The temperature-voltage characteristic thus automatically effected isselected for the typical duty cycle, load condition, and climatecontemplated for the particular model and, therefore varies the same waywith temperatures for all passenger vehicles of a given model. Suchuniform automatic adjustment is satisfactory from passenger car usagesthat are intermittent, such as commuting average distances, to thosethat are continuous for not more than a few days at a time such asvacation trips. However, where the duty cycles are intermittent orcontinuous for longer periods, or where the regulator is locatedremotely from the battery, the automatic adjustment of the voltageregulator may not provide a proper charging voltage for the battery.

Different fleets of vehicles operate under different conditionsrequiring that the battery charge state be altered to be commensuratewith the actual duty cycle. Thus, a fleet of trailer trucks drivencontinuously over highways at high speeds both day and night have adifferent duty cycle and corresponding battery charge state than a fleetof police cars or tax'icabs driven continuously at low speeds or a fleetof pickup and delivery trucks driven intermittently during just the day.The voltage regulator adjustment must be altered to reflect thesedifferent duty cycles, and temperature ambients in the localities inwhich such fleets operate must also be taken into account. Anotherfactor affecting the battery charge state is the nature and magnitude ofthe electrical loads to be supplied. Thus, buses have higher blower andheater requirements in the winter than in the summer, and rental fleetshaving air conditioners have different duty cycles than those without.Finally off-highway vehicles such as farm tractors, earth movingequipment, and even marine vessels all have different duty cyclesrequiring variable charge rates for the battery.

in order to satisfy the varying requirements of different vehicles itwould be possible to provide a specific alternatorregulator designed toprovide the proper charging voltage for a given application. Compared tothe economies of initial cost and part replacement, a better approach isto use a standardized alternator and vary the level of charging voltageeffected by the voltage regulator. However, as the voltage regulatorcontinues to decrease in size as through the use of integratedsemiconductor circuits, the circuits comprising the voltage regulatorbecome more inaccessible to external ad justment, especially where suchcircuits are first enclosed by protective encapsulants and then locatedwithin the housing of the alternator, the output of which is to beregulated and altered. The comparative economies of initial cost andpart replacement also favoring a standard regulator over a customregulator, it is desirable to have a regulator that is standard but yetaffords a capability allowing expedient adjustment of output voltage.Moreover, it is desired to allow such adjustments to be made both in thefield by the fleet user or in the factory by the manufacturer withoutremoving parts and housings from either the regulator or alternator andwithout requiring calibration meters and instruments. A still furtherdesirable feature is to provide the adjustment capability withoutintroducing an extra wire between the alternator and regulator orbetween the alternator and the rest of the electrical system of thevehicle, this feature being of added significance where a single cablebetween the alternator and battery is the only connection to the rest ofthe electrical system of the vehicle.

These features and others are provided not only collectively but alsoreadily and economically in the subject invention by a pluggable bodycontaining one or more series resistors. This body is removablyconnected to terminals of a standard voltage regulator located withinthe housing of a standard alternator. The terminals of the regulator areexposed to the exterior of the alternator housing by an opening throughwhich the body can be connected to the regulator and into which the bodymay be plugged and secured to the alternator housing. Moreover, a capcontaining a conductor may be connected to the body from the exterior ofthe alternator so as to short one or more resistances in the body,thereby effecting one or more alternator output voltages.

It is, therefore, a general object of this invention to provide aresistance removably connected across terminals of an otherwiseinaccessible voltage regulator for controlling the output voltage of analternator in a battery charging system.

It is another object of the present invention to provide a removablyconnected resistance of the type described wherein the portions ofresistance are shortable by means of a separately connectable conductor.

It is a further object of the present invention to provide a batterycharging system the output of which is adjustable by a removablyconnected and shortable resistance and wherein the only connections fromthe remaining electrical system of the vehicle are from the positive andnegative terminals of the battery.

It is still a further object of the present invention to provide a bodystructure having series resistance circuit contained therein, thecircuit having a first set of terminals removably connected withterminals of a voltage regulator for an alternator and a second set ofterminals connectable with a conductor embedded in a cap structurewhereby resistance in the body structure can be shorted by the conductorin the cap structure to vary the output of the alternator.

It is a further and more specific object to provide a body containing aresistance portions of which are shortable by a conductor in a cap,where the body has one set of terminals for removably connecting theresistance between a terminal of a regulator and a terminal of a batteryand another set of terminals for connecting an indicator lamp to anotherterminal of the regulator.

It is a further object and more specific object of the present inventionto provide a vehicular battery charging system comprised of a standardalternator and a standard regulator housed therein, where the output ofthe system is adjustable by shortable resistance means plugged into anopening in the alternator housing and removably connected therethroughto the regulator thereby to adapt a standard alternator and standardregulator to applications requiring different battery charge states.

It is another specific object of the present invention to alter theoutput voltage of an alternator having a regulator housed therein fromthe exterior of the alternator by selecting the position of a capinserted into a body containing shortable resistances, where the body isplugged into an opening in the housing of the alternator and removablyconnected therethrough to the terminals of the voltage regulator.

The novel features which we believe to be characteristic of ourinvention are set forth particularly in the appended claims. Ourinvention itself together with further objects and. advantages thereofwill be best understood by reference to the following description takenin connection with the accompanying drawings wherein:

FIG. 1 is a schematic diagram of a typical battery charging system theoutput of which may be altered by shortable resistances removablyconnected to terminals of a voltage regulator;

FIG. 2 is a schematic circuit of shortable resistances in a cap and bodyadapted to be removably connected with terminals of a regulator andhaving conductors for connecting with a vehicle battery and amalfunction indicator lamp;

FIG. 3 is a partial end view of an alternator end frame wherein the capand body of the subject invention are removably connected to terminalsof a voltage regulator shown through a broken away portion of the endframe of an alternator;

FIG. 4 is a top view of the cap of the subject invention located in anopening in the end wall of the alternator;

FIG. 5 shows a side view with parts broken away of the cap and body ofthe subject invention engaged in an opening through a partially brokenaway end wall of an alternator;

FIG. 6 is a perspective view of the cap and body of the subjectinvention with the cap disassembled therefrom;

FIG. 7 is a side view partially broken away of the body of the subjectinvention partially revealing various terminals, conductors, and legsfor engagement;

FIG. 8 is a plan view of the body partially broken away showing theconnection of resistors to each other and to the various terminals; and

FIG. 9 shows another body incorporating the features of the subjectinvention wherein additional conductors are connected to some terminalsto effect the circuit of FIG. 2.

The subject invention may be used in a motor vehicle battery chargingsystem of the type shown in FIG. 1 comprised of a battery 10, charged bya diode-rectified alternator 12, controlled by transistor voltageregulator 14, and adjusted as to output voltage by resistances containedin body 16 and shorted by a conductor in cap 18, all of which aredescribed in detail hereinafter. The negative terminal 20 of battery 10is here connected to ground 22 of a negative ground system, and thepositive terminal 24 is connected by cable 26 to the positive outputterminal 28 of alternator 12. Alternator 12 is comprised generally ofthree Y-connected stator windings 30a, 30b, and 300, the outputs ofwhich are connected to the respective legs of a three phase full wavebridge rectifier 32 and to the respective anodes of diode-trio 34. Withthe anodes of rectifier diodes 31 grounded at 22, the output of thealternator is applied both to terminal 28 connected to the cathodes ofthe rectifier diodes 33 and also to brush and slip-ring set 36 via thecommonly connected cathodes of diode-trio 34. Also connected toslip-ring set 36 is one end of the alternator rotor field winding 40,the other end of which is connected to brush and slip-ring set 38.

So that the average current through field winding 40 can be controlledto vary the output voltage of alternator 12, slip-ring sets 36 and 38are connected to voltage regulator 14 and the output of alternator 12 isapplied by a diode-trio34 to a voltage divider comprised of seriesresistances 42 and 44 in regulator l4 and resistances 46 and 48 in body16 removably connected to regulator terminals 50 and 52. In regulator14, capacitor 53 is connected between resistors 42 and 44 at a referencenode 54, which is connected in turn to the base of transistor Q1 viaZener diode 55. Biased from diode-trio 34 across resistor 56, the Q1collector is also connected to the base of output transistor Q3 and tobase biasing resistor 57 therefor. To complete the field circuit throughwinding 40, the Q2 collector is connected to slip-ring set 38 and the Q2emitter is grounded at 22. Moreover, a field discharge diode 58 isconnected across winding 40 as shown to protect the regulator circuitfrom the transient effects associated with the switching field current.

When the alternator output as sampled at reference node 54 fromdiode-trio 34 is sufficient to break down Zener diode 55 and thebase-emitter junction of transistor 01, transistor 01 is biased intoconduction, thereby grounding its collector and in the process the Q2base tied to it. This biases transistor Q2 non-conductive; and, thecurrent from diode-trio 34 through field coil 40 thus being interruptedby the cutoff of Q2, the field decays and the alternator output voltageas developed by stator windings 30 drops accordingly. When the outputvoltage drops, transistor Q1 will eventually be biased non-conductive.Transistor Q2 will now be biased fully conductive by base drive throughresistor 56. This cycle repeats such that transistor Q2 is switched onand off to maintain a predetermined voltage between terminal 28 andground as determined by the setting of voltage regulator 14.

The voltage required at node 54 to break down Zener 55 and thebase-emitter junction of transistor 01 is substantially constant for agiven regulator circuit of the type described. However, it may be seenthat the alternator output voltage may be varied by varying theresistance in the voltage divider between node 54 and tertninal 50.Thus, by adding any portion of the resistance in body 16, alternator 12must produce a higher output to produce the same breakdown potential atnode 54.

Body 16, the construction and engagement of which on alternator 12 willbe described more fully below with reference to FIGS. 3, 4, and 5,contains resistances that may be selectively added into the voltagedivider of regulator 14 to alter the output voltage of alternator 12.The circuit in body 16 is simply the series connection of conductors 43and 45, resistors 46 and 48, and conductor 49 between body terminals 60and 62, the latter being removably connected to regulator terminals 50and 52. Joining the connecting ends of the elements comprising theseries circuit are terminals 64, 66, 68, and 70 connecting respectivelyconductor 49 to resistor 48, resistor 48 to resistor 46, resistor 46 toconductor 45, an conductor 45 to conductor 43.

To effect maximum alternator output, terminals 60 and 62 of body 16 aresimple connected to regulator terminals 50 and 52 respectively. Cap 18containing conductor 72 therein and terminals 74 and 76 exposedtherefrom may thereafter be inserted into body 16 to short a portion ofthe series circuit therein and decrease the alternator accordingly.Thus, by inserting cap terminals 76 and 74 into any two adjacent bodyterminals 64, 66, 62, or 70, conductor 72 may assume one of the fourpositions 79b, 79c, 79d, or 79a on body 16 to short resistor 48,resistor 46, conductor 45, re all three respectively.

The circuit described above with respect to FIG. 1 is known as aone-wire system since there is just one connection between battery 10and alternator 12, this being cable 26 connected between batterypositive terminal 24 and alternator output terminal 28. With this systemthe output of the alternator, rather than the terminal voltage of thebattery, is sensed and maintained, and an ammeter may be connected inseries with the battery line 26 to indicate the charge and discharge ofthe battery relative to the output of the alternator. While connectionsare simplified with a single wire system without affecting performanceof the charging system, it may be desired in some applications to givethe driver of the vehicle an illuminated warning that some aspect of hischarging system has failed or to vary the alternator output inaccordance with variation of the battery terminal voltage. The latterbattery sensing feature might be desirable for instance where the outputcurrent of the alternator has such a magnitude that the voltage dropacross line 26 causes a difference between the alternator output andbattery terminal voltage beyond the range required for satisfactorycharging or where with load and age the voltage drop across thediode-trio 34 might vary unacceptably from that across rectifier diodes33.

A circuit affording battery sensing, warning indication, or both but yetalso the ready adjustment of alternator output afforded by the system ofFIG. 1 may be understood with reference to FIG. 2, which is amodification of a portion of the system shown in FIG. 1. In FIG. 2, thecircuit contained in a body 19 is identical to that shown contained inbody 16 of FIG. 1 with three exceptions: one is that conductor 43connected between body terminals 60 and 70 in FIG. 1 is removed; thesecond, that a new conductor 80 is connected between the body terminal70 and battery terminal 24; and the third, that new conductor 82connects an indicator lamp 84 and paralleling resistor 86 between bodyterminal 60 and one side of ignition switch 88, the other side of whichis also connected to battery terminal 24. Body 16 and cap 18 connectablethereto are otherwise identical in' configuration and connection toterminals 50 and 52 of regulator 14.

Although alternator 12 may be of other configurations, it is preferablyof the general type shown in the U.S Pat. to Newill et al. No 3,299,303,and accordingly it here has a housing 90 that encloses therein not onlya stator carrying windings 30 and a rotor carrying winding 50 but alsovoltage regulator 14, diode rectifier 32, diode-trio 34, and slip-ringsand brush sets 36 and 38. Similarly, while other regulation circuits inother configurations are also possible, regulator 14, as has beensuggested above, is here the integration of the circuit shown in FIG. 1onto one or more semiconductor chips. These chips are thereafterenclosed with a suitable encapsulant to provide the relatively thin,flat, and compact structure outlined in FIGS. 3 and S and preferablylocated, connected, and secured to alternator housing 90, slip-rings 36and 38, and ground 22 as shown in U.S. Pat. No. 3,538,362, by Robert A.Cheetham et al., and assigned to the same assignee as the assignee ofthe present invention.

Voltage regulator 14, the terminals 50 and 52 of which are accessible inopening 92 of alternator housing 90, is thus secured therein on a pad 94extending inwardly from end wall 96. Opening 92 is located at the cornerjuncture of alternator end wall 96 and side wall 98, where end wall 96has an outwardly facing lip 97, seen best in FIG. 5, bounding a portionof opening 92 and where side wall 98 has a slot 99, seen best in FIG. 4,communicating with opening 92.

Regulator 14 has three holes 13a, 13b, and 13c therethrough that allowscrews 17a, 17b, and 170 to urge surface of regulator 14 towards pad 94and housing end wall 96. Regulator 14 is thereby secured to alternatorhousing 90, and the heat generated within the regulator is allowed to beconducted first through and then from pad 94 which is finned for heatdissipation on its outer surface.

Holes 13a, 13b, and 13c have conductive eyelets 19a, 19b, and 190 platedthereabout on inwardly facing side 15. Eyelets 19a and 19b areconductively connected with terminal 50 and the Q2 collectorrespectively in regulator 14 and allow spadeended conductors 21a and 21bconnected with brushes 36 and 38 and spade-ended conductor 35 connectedwith diode-trio 34 to be pressed into contact by the heads of suitablyinsulated screws 17a and 17b. The shanks of these screws are firstinserted through holes 13a and 13b and then threaded into holes 23a and23b of end wall 96. Also threaded into end wall 96 is a third screw 17cinserted through hole 130 to connect externally grounded housing 90 witheyelet 190 that communicates with ground 22 of circuit 14.

The secured engagement of body 16 in alternator opening 92 as well asthe construction of body 16 and cap 18, may best be understood withreference to FIGS. 5, 6, 7, and 8, wherein elements corresponding tothose shown in FIG. 1 are given like designators. As seen in FIGS. 4 and6, cap 18 is comprised generally of a conductor 72 embedded in a moldedinsulating material 73 and having male terminals 74 and 76 protruding atright angles therethrough. A hub 77 extends in the direction ofterminals 74 and 76, and a top 78 has embossed thereon the instructionsPULL OUT TO SET VOLTAGE and also arrows LO 79a, 2" 79b, 3 790, and HI79d, pointing outwards along the respective sides of the square cap asseen in FIG. 4.

As seen in FIGS. 6 and 7, body 16 is formed of a moldable insulatingmaterial so as to define a generally cubed-shaped structure bounded bysides 106, 108, 110, and 112, atop 114. and a bottom 116. Protrudingfrom side 106 is a ledge 118 supporting a ramp 120 of sloped heightincreasing from bottom 116 to top 114 and dropping abruptly to the ledge118 at surface 122. Ledge 118 fits into slot 99 of housing opening 92,as seen in FIG. 4, with the effect that after the insertion of ramp 120into slot 99, ramp surface 122 locks against the interior or alternatorside 98, as seen in FIG. 5. Bottom 116 of body 16 has a channel 128therethrough defining legs 130 and 132, the latter having a lip 134protruding towards channel 128. After body 16 is inserted into opening92 so that legs I30 and 132 straddle end wall 96, male terminals 50 and52 of regulator 14 project into female terminals 60 and 62 of body 16,and leg lip I34 engages wall lip 97 protruding outwardly from end wall96. Body 16 is thus plugged snugly into and secured to housing at threeplaces: first, against the inside surface of side 98 by the lockingaction of ramp surface 122; second, at end wall 96 by the snapping ofleg lip 134 over end wall lip 97; and third, against regulator 14,itself fastened to end wall 96 by a pad 94, by the interaction ofregulator terminals 50 and 52 with body terminals 60 and 62.

The internal construction of body 16 may be best understood withreference to FIGS. 7 and 8, wherein six female connector terminals 60,62, 64, 66, 68, and 70 are shown encapsulated within body 16. Connectors60 and 62 are located in leg 130 paralleling side 106 and may beremovably connected through alternator opening 92 to engage maleterminals 50 and S2 of regulator 14. To receive male connectors 74 and76 of conductor plate 72 in cap 18, female terminals 64, 66, 68, and 70in body 16 are exposed through top 114 defining thereon a square-likepattern wherein one terminal extends from a corner of each side to aboutthe middle. To environmentally protect male terminals 74 and 76 of cap18 and female terminals 64, 66, 68, and 70, a lip encompasses the latteron body 16 and seals against hub 77 of cap 18 upon insertion of cap 18into body 16. Moreover, since cap 18 could be inserted into one of fourpositions on body 16, a raised marking 102 in the form of an arrowpointing inwardly from side 106 is also located on top 114 to allowcorrespondence with raised arrows 79 on cap 18.

As best seen in FIG. 8, the series circuit contained within body 16 iscomprised of conductor 49 secured between connectors 62 and 64; resistor48, between connectors 64 and 66; resistor 46, between connectors 66 and68; conductor 45, between connectors 68 and 70; and conductor 43 betweenconnectors 70 and 60. Thus, any two adjacent terminals of this seriescircuit exposed through surface 114 by connectors 64, 66, 68, and 70 canbe short circuited by the roper positioning and insertion of terminals74 and 76 of cap 18 to alter the resistance developed across bodyterminals 60 and 62 and applied to regulator terminals 50 and 52. Topermit up to four different voltage settings of equal steps to beeffected, the value of resistor 48 is selected to be twice that ofresistor 46 giving a total series resistance in body 16 from zero up tothree times the value of resistance 46. Therefore, with cap 18positioned so that cap arrow LO 79a corresponds with body arrow 102,male terminals 74 and 76 short circuit connectors 64 and 70. Theresistance applied between body terminals 60 and 62 will be zero, andregulator 14 will be configured to cause alternator 12 to produce itsminimum output. When cap 18 is positioned so that arrow 2 79bcorresponds with body arrow 102, connectors 64 and 66 will be shorted toshort resistor 48. The total resistance across body connectors 60 and 62is then just that of resistor 46. When positioned at 3 790, connectors66 and 68 are shorted to short resistor 46 causing only resistance 48 toappear at connectors 60 and 62. Finally, when positioned at 111" 79d,terminals 68 and 70 are shorted to short conductor 45 so that the sum ofresistances 46 and 48 appears across connectors 60 and 62, therebyconfiguring regulator 14 to cause alternator 12 to produce its highestoutput. Since the latter output would be obtained without cap 18 beinginserted into body 16, HI position 79b on cap 18 may be seen to serve atleast two purposes in addition to any voltage change introduced by theresistance of conductor 72. The first is to provide a resting place forcap 18 in a position where it avoids inadvertent misplacement and yetdoes not affect alternator output. Secondly, by permitting the cap 18 tobe always kept on and sealed within body 16, cap 18 assures thecontinual environmental protection of body terminals 64, 66,

68, and 70 as well as cap terminals 74 and 76 regardless of setting.

In a charging system for the 12-volt negative-ground battery for atypical passenger vehicle, the automatic thermistor compensatedregulator obtains alternator outputs varying from 13.4 to 14.2 voltswith decreasing battery temperatures. However, the standard regulatorused with the voltage adjustment package of the subject invention,rather than having thermistor compensation, would be set to produce aslightly lower alternator output of 13.2 plus or minus 0.2 volts thatwould be flat compensated" to be constant over a temperature range from40 to 200 F. By then selecting resistors 46 and 48 to have values of Iand 200 ohms respectively and shorting these with cap 18, the 13.2 voltalternator output effected by this standard flat-compensated regulatorcould be increased to 14.4 volts in three 0.4 volt steps.

Body 19, shown in FIG. 9, contains therein a series circuitcorresponding with that shown in FIG. 2 and described above with respectthereto. However, conductors 80 and 82 instead of being connecteddirectly with battery terminal 24 and indicator lamp 84, as shown inFIG. 2, are provided with male terminals 81 and 83 as shown in FIG. 7for subsequent connection with corresponding female terminals (notshown) to the battery and indicator lamp.

Having described two embodiments of the present invention, it isunderstood that the specific terms and examples are employed in adescriptive sense and not for the purpose of limitation. Otherembodiments of the invention may be practiced as, for instance, with apositive ground battery charging system. We, therefore, intend in theappended claims to cover such modifications and changes as fall withinthe true scope of our invention.

What we claim as new and desire to secure with letters patent of theUnited States is:

l. A voltage regulated power supply system for feeding electrical loadson motor vehicles or the like comprising:

a. a generator having a generator housing including an interior cavity,an end wall defining one end of said cavity, and an opening through saidend wall communicating with said cavity, said generator having an outputwinding and a field winding located in said cavity; means connected withsaid output winding providing first and second direct current fieldenergizing terminals;

c. a voltage regulator including a regulator housing secured to said endwall in said cavity, an output transistor located within said regulatorhousing, a voltage divider comprised of at least one impedance disposedwithin said regulator housing and operative connected to said outputtransistor to control the conduction thereof in accordance with thevoltage applied to said voltage divider, first and second voltageregulator terminals connecting the interior and exterior of said voltageregulator housing and extending towards said opening, means connectingsaid first regulator terminal with said first field energizing terminal,

means connecting said transistor and said field winding in seriesbetween said first voltage regulator terminal and said second fieldenergizing terminal, and means connecting said voltage divider with saidsecond voltage regulator terminal;

(1. a voltage adjustment device including a housing secured in saidopening by a pair of legs straddling said end wall, a plurality ofseries connected resistors contained within said housing, first terminalmeans connected respectively with the junctions of said resistors,second terminal means connected with the ends of the series circuitformed by said resistors, said second terminal means located in one ofsaid straddling legs complementary to said voltage regulator terminalswhereby said adjustment device is removably secured to said voltageregulator terminals, and;

e. a shiftable cap member containing a conductor removably connectedfrom the exterior of said cavity to various pairs of said firstterminals and operative to selectively short circuit certain of saidresistors to thereby adjust the resistance between said voltageregulator terminals and thereby adjust the output voltage of saidsystem.

2. In a battery charging system for vehicles including a generatorhaving an output winding and a field winding:

a. a voltage regulator contained within a housing and comprised of firstand second terminals connecting the interior and exterior of saidhousing, means disposed within said regulator housing connecting saidoutput winding with said first terminal thereby providing direct currentpotential thereto, an output transistor contained within saidregulatorhousing, said first terminal and said output transistorconnected in circuit across the field winding of the generator, and avoltage divider contained within said housing and comprised of at leastone impedance connected to said second terminal and defining a nodetherebetween, said node being operatively connected to said outputtransistor to control the conduction thereof in accordance with thepotential at said node;

b. a connector body comprised of a circuit comprised of at least oneresistor, first, second, third and fourth terminals, said first terminalof said body removably connected with said first terminal of saidregulator, said second terminal of said body connected to the one sideof said resistor and removably connected to said second terminal of saidregulator, said third terminal of said body connected with said one sideof said resistor, and said fourth terminal of said body connected withthe other side of said resistor, a first conductor one end of which isconnected to said first terminal and the other end of which is adaptedto be connected in circuit with the ignition switch of a vehicle, and asecond conductor connected to said other side of said resistor andadapted to be connected in circuit with the battery being charged bysaid system, and;

. a cap structure containing a circuit therein, said cap circuitconnected with first and second terminals adapted to be removablyconnected with said second and third terminals of said body, thereby toalter the resistance connected between said first and second terminalsof said regulator.

mg UNITED STATES- PATENT OFFICE C CERTIFICATE OF CORRECTION Patent No-3,659,188 Da ed April 25; 1972 I nventofls) Arthur W. Alexander, Glen R.Renner It is certified that error appears in the above-identified patentand that said Letters Patent are hereby corrected as' shown below:

a" I v I Column 3, Line 70, "Q3" should read Q2 Column 7, Line 55,"operativef should read operatively Signed and sealed this lhth day ofNovember 1972.

(SEAL) Attest:

EDWARD M.FLETCHER,JR. v ROBERT GOTTSCHALK Attesting Officer Commissionerof Patents v UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTIONPatent No. 3,659,188 I Dated April 25, 1972 ln fl Arthur W. AlexandenGlen R. Relrmer It is certified that error appears in theabove-identified patent and that said Letters Patent are herebycorrected as' shown below:

Column 3, Line 70, "Q3" should read Q2 Column 7, Line 55, "operativefshouldread operatively Signed and sealed this ll th day 'of November1972.

(SEAL) Attest: I

EDWARD M.FLETCHER ,JR. 7 ROBERT GOTTSCHALK Commissioner of PatentsAttesting Officer

1. A voltage regulated power supply system for feeding electrical loadson motor vehicles or the like comprising: a. a generator having agenerator housing including an interior cavity, an end wall defining oneend of said cavity, and an opening through said end wall communicatingwith said cavity, said generator having an output winding and a fieldwinding located in said cavity; b. means connected with said outputwinding providing first and second direct current field energizingterminals; c. a voltage regulator including a regulator housing securedto said end wall in said cavity, an output transistor located withinsaid regulator housing, a voltage divider comprised of at least oneimpedance disposed within said regulator housing and operative connectedto said output transistor to control the conduction thereof inaccordance with the voltage applied to said voltage divider, first andsecond voltage regulator terminals connecting the interior and exteriorof said voltage regulator housing and extending towards said opening,means connecting said first regulator terminal with said first fieldenergizing terminal, means connecting said transistor and said fieldwinding in series between said first voltage regulator terminal and saidsecond field energizing terminal, and means connecting said voltagedivider with said second voltage regulator terminal; d. a voltageadjustment device including a housing secured in said opening by a pairof legs straddling said end wall, a plurality of series connectedresistors contained within said housing, first terminal means connectedrespectively with the junctions of said resistors, second terminal meansconnected with the ends of the series circuit formed by said resistors,said second terminal means located in one of said straddling legscomplementary to said voltage regulator terminals whereby saidadjustment device is removably secured to said voltage regulatorterminals, and; e. a shiftable cap member containing a conductorremovably connected from the exterior of said cavity to various pairs ofsaid first terminals and operative to selectively short circuit certainof said resistors to thereby adjust the resistance between said voltageregulator terminals and thereby adjust the output voltage of saidsystem.
 2. In a battery charging system for vehicles including agenerator having an output winding and a field winding: a. a voltageregulator contained within a housing and comprised of first and secondterminals connecting the interior and exterior of said housing, meansdisposed within said regulator housing connecting said output windingwith said first terminal thereby providing direct current potentialthereto, an output transistor contained within said regulator housing,said first terminal and said output transistor connected in circuitacross the field winding of the generator, and a voltage dividercontained within said housing and comprised of at least one impedanceconnected to said second terminal and defining a node therebetween, saidnode being operatively connected to said output transistor to controlthe conduction thereof in accordance with the potential at said node; b.a connector body comprised of a circuit comprised of at least oneresistor, first, second, third and fourth terminals, said first terminalof said body removably connected with said first terminal of saidregulator, said second terminal of said body connected to the one sideof said resistor and removably connected to said second terminal of saidregulator, said third terminal of said body connected with said one sideof said resistor, and said fourth terminal of said body connected withthe other side of said resistor, a first conductor one end of which isconnected to said first terminal and the other end of which is adaptedto be connected in circuit with the ignition switch of a vehicle, and asecond conductor connected to said other side of said resistor andadapted to be connected in circuit with the battery being charged bysaid system, and; c. a cap structure containing a circuit therein, saidcap circuit connected with first and second terminals adapted to beremovably connected with said second and third terminals of said body,thereby to alter the resistance connected between said first and secondterminals of said regulator.